Diaphragm-horn.



M. R. HUTGHISON.

DIAPHRAGM HORN.

- APPLICATION FILED AUG.14, 1914.

1,120,057. Patented Dec.8,1914.

WITNESSES I INVE NTOR v By W ATTORNEY UNITED STATES rATENT orurron.

MILLER REESE HUTCHISON, 0F WEST ORANGE, NEW JERSEY, ASSIGNOR TO LOVELL- MOCONNELL MANUFACTURING COMPANY, CORPORATION OF DELAWARE.

DIAPHRAGM-HORN.

Specification of Letters Patent.

Patented Dec. 8, 1914.

Original application filed October 26, 1909, Serial No. 524,762. Divided and this application filed August 14,

1914. Serial No. 856,826.

To all whom it may concern Be it known that I, MILLER REESE HUTCHI- SON, a citizen of the United States, and a resident of West Orange, in the county of Essex and State of New Jersey, have invented certain new and useful Improve ments in Diaphragm-Hornsof which the following is a specification.

My present invention relates to horns or signaling devices wherein a vibratory member such as a diaphragm is actuated by power derived from a rotary member or drive shaft, which may be the armature shaft of an electric motor.

In my prior Patents Nos. 923,048, 923,049, and 923,122, I have disclosed various means through which movement of a rotary member may be applied to vibrate a diaphragm, so that only a part of the movement of the diaphragm is forced by the driving means, the diaphragm being permitted any desired degree of independent motion preferably on both sides of normal.

In my parent application Serial No. 524,762, filed October 26, 1909, and of which the present application is a division, I have described an arrangement of parts whereby thevibratory motion of the diaphragm may be derived from a drive shaft, when such shaft is arranged at an angle to the plane of the diaphragm instead of parallel therewith. This is particularly desirable in the cases where the armature shaft of an electric motor is utilized as the drive shaft, since it permits a compact arrangement of the motor within a case which need not extend peripherally outside of the circumference required for inclosing the diaphragm.

In the specific arrangement forming. the subject of the present application, the shaft is presented endwise to the diaphragm and is either perpendicular or at a high angle to the diaphragm and is arranged eccentrically therewith so that its axis does not pass through the center of the diaphragm. With the latter arrangement the diaphragm may have a comparatively small weariece at its center. and presenting a straight line contact surface with which the cams on the face of the rotor may successively engage in the most effective manner, and the reaction of the diaphragm on the motor may be taken up by the thrust bearing of the shaft rather than in resistance lateral movement or bending of the shaft. ture shaft of an electric motor, the latter may be mounted in a casing eccentric to the diaphragm but its size may not be so great but what it may be disposed entirely within the rearward projection of the periphery of the diaphragm.

When the device is secured in position with the axis of the diaphragm horizontal, I preferably drop the motor down but keep its axis in'the same vertical plane as the axis of the projector. Thus the center of gravity of the device is low and the device more stable, with less strain on its support, while the projector is on a higher level and hence somewhat better adapted to project the sound clear of any interferingsub-structure of the automobile.

Having thus described the nature of my invention, I will now describe one practical embodiment thereof in connection with the accompanying drawing which shows a vertical section longitudinally of the drive shaft.

In the drawing the horn or resonator 1, front case 2, peripheral flange 3, diaphragm 4, clamps, 5, 6, and cork-like gaskets 7, 8, are of any known construction and are in fact similar to one of the forms shown in my prior application, Serial No. 494,120, filed May 5, 1909. The wear-piece 9, secured to the center of the diaphragm, may be of any known or approved construction, but is preferably formed for straight line contact with the rotary displacing member. The drive shaft 10 carries the rotary member 11 provided with teeth or projections 12,

the latter being face cam projections, preferably cut in accordance with the well known principles similar to those established for teeth of bevel or crown gears, at least so far as concerns making their sliding engage- If the shaft be the armament with the diaphragm projection 9, so that it will not vary much from line of con tact.

In the form shown the drive shaft 10 is the shaft of armature 13 energized through brushes 14. and commutator '15, rotating within the field of pole pieces 16, 17 energized by coils 18, 19. The motor may be any suitable rotary motor, though for most purposes I prefer a low voltage direct current motor adapted to rotate always in one direction, regardless of the polarity of the current supplied thereto.' The drive shaft is eccentric to the diaphragm by an amount determined by and substantially equal to the radius of the face cam; hence if the motor frame be symmetrical in respect to its own axis as shown, and if the case 20 be no larger than isnecessary to inclose the motor,

the construction will be somewhat eccentric with respect to the diaphragm and the horn section of the case. As previously pointed out, the eccentricity of the motor is in a downward direction so that the axis of the motor and of the projector are in the same vertical plane and in the direction 'ofthe line contact surface of the wear-piece. The lowering of the center of gravity of the motor somewhat reduces the leverage tending to loosen or bend any bracket or other form of support for the horn. Obviously, the motor case may be made symmetrical by making it larger than is necessary, and the eccentricity of the motor may be decreased by decreasing the diameter of the face cam.

The motor frame is shown as secured in the case by screws 21, 22, and the armature shaft 10 carrying the face cam 11 is prevented from endwise displacement by means of a thrust bearing 23, which is preferably mounted upon and formed integral with a set screw 24 provided with a lock nut 25 In order toinsure firm contact of the shaft cam with its thrust hearing I may displace the armature longitudinally of its "shaft in the direction of the diaphragm so that the solenoid action of the motor field will draw the shaft rearwardly as far as permitted by the thrust bearing although other means might be employed for accomplishing this result. This affords the simplest possible means for adjusting the cam with respect to the diaphragm projection so as to secure the best results.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent, is

1. In an alarm or signaling device, a diaphragm, mechanical means for bodily displacing the center portion of the diaphragm to cause bodily vibration thereof, said means being located entirely in the rear of the plane of the diaphragm, and including an electric motor and a drive shaft constituting 2. In an alarm or signaling device, a dia phragm, a diaphragm case, and mechanical means for vibrating said diaphragm located within the rearward projection of the periphery of the diaphragm case, and including a high speed electric motor having its armature disposed substantially at right angles to the plane of the diaphragm and eccentric to a line perpendicular to the diaphragm at its center, and means on said shaft for repeatedly forcing the center of said diaphragm bodily out of its normal plane upon the rotation of said shaft.

3. In an alarm or signaling device, a diaphragm, a wear piece or impulse receiving portion, and mechanical means for vibrating the diaphragm including an electric motor, and a drive-shaft having a face cam acting on said wear piece, in combination with means for supporting said drive shaft substantially at right angles to theplane of the diaphragm and eccentric to a line perpendicular thereto, passing through the axis of said wear piece, said eccentricity and the radius of said face cam being interdependent.

4. In an alarm or signaling device, a diaphragm, a wear piece or impulse receiving portion, and mechanical means for vibrating the diaphragm, including an electric motor, a drive shaft constituting an extension of the motor shaft and disposed substantially at right angles to the plane of the diaphragm and eccentric to a line perpendicular thereto, and passing through the center of said wear piece, and a face cam carried by said shaft, the amount of said eccentricity determining the effective radius of said face. cam.

5. In an alarm or signaling device, a diaphragm, a wear piece or impulse receiving portion, and mechanical means for vibrating the diaphragm located entirely in the rear of the plane of the diaphragm and including a drive shaft disposed substantially at right angles to the plane of the diaphragm and eccentric to a line perpendicular thereto, and. passing through the center of said wear piece, and a face cam carried by said shaft, the amount of said eccentricity determining the effective radius of said face cam.

6. In an alarmor signaling device, a diaphragm, mechanical means including a drive shaft, and a rotor thereon presenting face projections adapted to contact with said diaphragm in a direction to produce bodily motion of a center portion thereof in a direc-' time having a Component parallel with the Ill axis of said shaft, said shaft being positioned perpendicularly to the diaphragm and eccentric to a line passing through the center thereof.

7. In an alarm or signaling device, a diaphragm, a wear piece or impulse receiving projection thereon at the center, and presenting a straight line contact surface, and mechanical means for vibrating the diaphragm including a drive shaft'clisposed at right angles to the plane of the diaphragm and eccentric to a line perpendicular thereto passing through the center of said wear piece, and a head carried by said. shaft and having a series of projections on the face thereof toward said diaphragm and adapted to successively engage with said wear piece, the distance of said last mentioned projections from the center of rotation, being substantially equal to the eccentricity of said shaft in respect to said wear piece, and the eccentricity of said shaft being substantially in the direction of the contact line of said wear piece.

the diaphragm out of its normal plane, and

means for advancing one 'of said above mentioned parts toward the other to vary the extent of the forced movement of the diaphragm.

9. In an alarm or signaling device, a diaphragm, an impulse receiving part thereon at the center thereof, an actuating part in the form of a head rotatable ina plane substantially parallel to said diaphragm and about an axis eccentric to the axis of the diaphragm through said first mentioned part, and having a series of cam projections on the face thereof toward said diaphragm, and adapted to successively engage with the outer face of said first mentioned part away from said diaphragm to force the center of the diaphragm out of its normal plane, and an adjustable set screw in axial alinement with said head, and constituting a thrust bearing.

10. In an alarm or signaling device, :1 diaihra m an 1m ulse I'QCGIVIDO art thereon i at the center, an electric motor having its ried by said shaft and adapted to engage with said impulse receiving projection for imparting bodily vibrations to the center portion of said diaphragm, a diaphragm casing part and a motor casing part projecting rearwardly therefrom and eccentric in respect to the latter.

11. In an alarm or signaling device, a diaphragm, a pair of opposed diaphragm clamping members, one of said members having a sound outlet opening therethrough concentric with the diaphragm and the other of said members carrying a rcarwardly extending cylindrical motor casing eccentrically disposed in respect to said diaphragm, a motor within said casing having its armature shaft presented endwise to said diaphragm, a wear piece on said diaphragm at the center of the latter and a face cam carried by said armature shaft and engaging with said wear piece, the eccentricity of said motor casing in respect to said diaphragm being substantially equal to the effective radius of said face cam.

12. In an alarm or signaling device, a diaphragm, a pair of opposed diaphragm clamping members, one of said members having a sound outlet opening therethrough concentric with the diaphragm and the other of said members carrying a rearwardly ex tending cylindrical motor casing eccentrically disposed in respect to said diaphragm, a motor within said casing having its armature shaft presented endwise to said diaphragm, a wear piece on said diaphragm at the center of the latter, a face cam carried by said armature shaft and engaging with said wear piece, the eccentricity of said motor casing in respect to said diaphragm being substantially equal to the effective radius of said face cam, and means for ad justing the armature shaft and rotor axially to vary the degree of over-lap of the face cam projections on said wear piece.

13. An alarm or signaling device, a diaphragm, a pair of opposed diaphragm clamping members, one of said members having a sound outlet opening, a substantially cylindrical high speed electric motor carried by the other of said members and having its axis at right angles to said diaphragm and eccentrically disposed in regard thereto, and a face cam carried by said shaft for vibrating said diaphragm, said face cam being of an effective radiussubstantially equal to the eccentricity of said motor in respect to said diaphragm.

14. An alarm or signaling device, a diaphragm normally disposed substantially vertically, a pair of opposed diaphragm clamping members, one of said members having a horizontally disposed projector concentric therewith, a substantially cylindrical high speed electric motor carried by the other of said members and having its axis at right angles to said diaphragm and disposed below the axis of said diaphragm, and a face cam carried by said shaft for vibrating said diaphragm, said face cam being of an effective radius substantially equal to the distance between the axis of said motor, and the axis of said diaphragm.

mama? Signed at Exeelsior, in the county of Hennepin and State of Minnesota, this 10th day 10 of Aug. 1914!:-

MILLEJR REESE HUTCHISONL Witnesses:

W. P. HUTGHISON, M. P. HUTGHISON. 

